I want to find questions that were closed because they were off-topic. So far the best I have been able to do is to search for closed:1 duplicate:no which finds questions that were closed, but not for being duplicates. Most of these seem to be "unclear what you are asking", and there does not seem to be any way to tell what the closure reason was without opening the individual pages. I can see the question titles, but very few are obviously off-topic.
Is there some way to find off-topic questions more efficiently?